The only time you should ever split profits is if you have no money up. If you can fund a prop account ($25,000), then you should NEVER accept less than a 100% payout.
Do your homework and get the best deal (this doesn't just mean rates...it means software, news, benefits, etc) .
I would read threw the different threads about prop. firms...then contact all of them. Get a good idea about what they are all about. Then go with whom ever you feel the most comfortable. The are very good deals out there. Good luck